Currently, food products, cosmetics, or drugs are generally manufactured with adding antioxidants or antiseptic agents for preventing oxidation or multiplication of bacteria in the products in order to maintain quality of the products as long as possible. Manufacturing products with the antioxidants or the antiseptic agents added therein is one of effective measures for increasing life of the products, enhancing value of the products, and hence contributing to industrial growth. However, in recent years, there is an increasing demand for using food products or the like in a state as natural as possible without the antioxidants or the antiseptic agents therein.
In order to restrain oxidation of the food products or multiplication of bacteria without adding the antioxidants or the antiseptic agents, measures such as manufacturing a container capable of preventing outside air from entering into the container and encapsulating the food products or the like in such a container for use may be taken. Examples of such measures in the related art are disclosed in Japanese Unexamined Patent Publication No. 2002-2755 (hereinafter referred to as Patent Document 1) and U.S. Pat. No. 6,536,631 (hereinafter referred to as Patent Document 2).
In Patent Document 1, a container “including a container body having resiliency and being formed with a discharging port at one end, an inner plug provided for closing the discharging port, an inner plug projection provided at a center of the inner plug and projecting outwardly from the discharging port, a through-hole provided in the inner plug for communicating the inside and the outside of the container body, and a nozzle member having resiliency and coming into tight contact with the peripheral edge of the discharging port and the side surface of the inner plug projection” is disclosed.
In Patent Document 2, a container having a reservoir for storing contents, and a head for discharging a predetermined amount of liquid from at least one outlet port is disclosed.
However, in the container of Patent Document 1, since the inner plug projection and the resilient nozzle member are simply in line contact with each other in the discharging direction, tight contact between the nozzle member and the inner plug projection is insufficient, and hence sufficient backflow preventing function cannot be achieved.
In the container according to Patent Document 2, since the head and the reservoir are formed integrally, the shape is complex, and hence it is difficult to manufacture.
Therefore, it is an object of the present invention to provide a backflow preventing plug for a container, the container, and a pouring device in which a container body and a plug member are separately formed in simple shapes and tight contact between the plug member and a resilient member is enhanced to improve the backflow preventing function.